Tühikäiguklapp

Tühikäiguklapp, also known as an idle air control valve (IACV), is a component found in many internal combustion engines, particularly those with electronic fuel injection. Its primary function is to regulate the engine's idle speed. When the engine is idling, meaning it's running without the accelerator pedal being pressed, the throttle plate is nearly closed, restricting airflow. The tühikäiguklapp bypasses this closed throttle plate, allowing a controlled amount of air to enter the engine. This bypass air is crucial for maintaining a stable and consistent idle RPM, preventing the engine from stalling.

The tühikäiguklapp is typically controlled by the engine control unit (ECU). The ECU monitors various engine parameters, such as engine temperature, load, and RPM, and adjusts the position of the tühikäiguklapp accordingly. For instance, when the engine is cold, the ECU may command the valve to open more to provide a higher idle speed for smoother operation until the engine reaches its optimal operating temperature. Conversely, as the engine warms up, the ECU will gradually close the valve to lower the idle speed to its designed level.

A malfunctioning tühikäiguklapp can lead to several drivability issues. These may include an unstable or rough idle, a stalling engine, or an engine that idles too high or too low. It can also affect fuel economy. Diagnosing a faulty tühikäiguklapp often involves checking for electrical faults, obstructions in the air passage, or the valve's mechanical operation. Cleaning or replacing the tühikäiguklapp is a common repair to address these problems.